ASTM D3336 Life of Lubricating Greases in Ball Bearings at Elevated Temperatures
The test evaluates the endurance life of greases in ball bearings at high speeds and high temperatures. An SAE No. 204 Bearing in rotated at 10,000 rpm at test temperatures of 250°F to 400°F depending on the grease type. Navy type spindles (Pope Machinery Corp.) have a thrust load of 5 pounds and a radial load of 5 pounds applied to the bearing. The test cycle is closed 20 hours on and 4 hours off for the test temperature above 300°F and 22 1/2 hours on and 2 1/2 hours off for the test 300°F and below.
The test result is the number of cumulative hours the bearing will run without exceeding the motor over-load set point, torque overload set point, or over temperature limit.